Results 51 to 60 of about 24,711 (273)
Topographic Effects in Geoid Determinations
Geosciences, 2018 Traditionally, geoid determination is applied by Stokes’ formula with gravity anomalies after removal of the attraction of the topography by a simple or refined Bouguer correction, and restoration of topography by the primary indirect topographic ...
Lars E. Sjöberg
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MARINE GEOID UNDULATION ASSESSMENT OVER SOUTH CHINA SEA USING GLOBAL GEOPOTENTIAL MODELS AND AIRBORNE GRAVITY DATA [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016 Global geopotential models (GGMs) are vital in computing global geoid undulations heights. Based on the ellipsoidal height by Global Navigation Satellite System (GNSS) observations, the accurate orthometric height can be calculated by adding precise and ...
N. M. Yazid +6 more
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Eos, Transactions American Geophysical Union, 1989 The International Geoid Commission was formed by the International Association of Geodesy at the 19th General Assembly of the IUGG in Vancouver, 1987. The commission operates as Commission XII of Section III (Determination of the Gravity Field) of IAG.A Commission of the IAG considers those activities for which close international cooperation or ...
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Geophysical Research Letters, Volume 52, Issue 24, 28 December 2025.Abstract By analyzing velocity changes of the Pine Island Ice Shelf (PIIS) from October 2014 to August 2025 using Sentinel‐1A/B imagery, we find that the PIIS flow changed markedly over this period. A distinct slowdown occurred at the central PIIS from 14 March 2022 to 20 January 2023, during which velocities decreased from 13.15 ± 0.04 to 12.71 ± 0.17
Yite Chien, Chunxia Zhou, Bryan Riel
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Near-zone Direct and Indirect Topographic Effects Based on the Rectangular Prism and Surface Element [PDF]
Journal of Geodesy and Geoinformation Science, 2019 Helmert’s second method of condensation is an effective method for terrain reduction in the geoid and quasi-geoid determinations. Condensing the masses outside the geoid to a surface layer on the geoid produces several forms of topographic effects ...
Jian MA,Ziqing WEI,Zhenghui YANG,Xiaogang LIU,Jianfeng JI
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Monitoring Pacific walrus coastal haulouts by satellite to estimate herd abundance and distribution
Wildlife Society Bulletin, Volume 49, Issue 4, December 2025.We monitored Pacific walrus haulouts with drone and satellite imagery to derive new methods for estimating minimum population size. The largest herd observed during an 8‐year study period was on the coast of northeastern Russia at Cape Serdtse‐Kamen in autumn 2022 where the aggregation spanned over an area of 184,094 m2 with a mean density (and 90 ...
Anthony S. Fischbach +2 more
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Terrestrial, Atmospheric and Oceanic Sciences, 2013 In this paper we present the concepts and realization of the shallow-layer Shen geoid determination method, which is quite different from the classical geoid modeling methods (Stokes¡¦ method, Molodenskii¡¦s method, etc.), for determining the global or ...
WenBin Shen Jiancheng Han
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Height determination using GPS data, local geoid and global geopotential models [PDF]
, 1995 Orthometric heights are normally derived using the spirit levelling. This requires the spirit level equipment to be set up from point 10 point along a levelling line which is a time consuming and tedious task.
Abdullah, Khairul Anuar
core
A benchmark study on mantle convection in a 3-D spherical shell using CitcomS [PDF]
, 2008 As high-performance computing facilities and sophisticated modeling software become available, modeling mantle convection in a three-dimensional (3-D) spherical shell geometry with realistic physical parameters and processes becomes increasingly feasible.
Gurnis, Michael +4 more
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Gravimetric geoid model determination of Central Ukraine area using combination of LSC and truncated SHA methods [PDF]
, 2023 Bohdan Dzhuman
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